Your baby's vision, movement and touch are working in harmony
Your baby will have been able to focus on objects close to them, and as their vision developed will have started to look at and follow nearby objects with their eyes. Now, they are beginning to use what they see and their developing sense of their body to look at and reach towards an object.
This involves depth and distance perception
Your baby's vision at birth vision was blurred and they won't have been able to judge distance accurately, as this involves processing binocular information, that is, information from both eyes.[1]
However, your baby will have since started to be able to process binocular information and will, as their physical skills develop, begin to use this information when reaching towards an object.[2]
You'll notice that your baby will look towards an object before reaching for it. At first, they might not reach accurately, but as they begin to link information from what they see with what they feel as they touch the object, they will develop their perception of distance and reach more accurately.
What they see is coming together with movement and touch
Looking towards an object and then reaching for it helps your baby to link what they see with their movement and what they feel as they touch the object. Your baby will practise reaching many times and as they do this become more accurate as they reach for objects.
Looking at, reaching for and grasping objects is an important part of your baby’s developing hand-eye coordination as well as providing opportunities for them to explore objects and learn more about the world.
They will eventually reach an object without needing to look at it
When your baby first starts to reach towards objects, they will use their developing vision to help them to reach accurately. However, as they become more skilled and develop more awareness of their body, they will be able to reach and grasp an object without looking at it.[3]
And then the smaller, further away things will come into view
Your baby will continue to develop accuracy when they reach for objects, and as their vision develops, they will be able to look at objects and people that are further away and will notice small things that are close to them.
References:
[1] Ekberg, T.L, Rosander, K. von Hosten, C., Olsson, U. Soska, K.C., Adolph, K.E. (2013) ‘Dynamic reaching in infants during binocular and monocular viewing.’ Experimental brain research. 229. Pp1-12.
[2] Braddick, O., Atkinson, J. (2011). ‘Development of human visual function.’ Vision Research. 51(2011) pp. 1588-1609.
[3] Crowley, K. (2017) Child Development. A Practical Introduction (2nd edn). London: Sage.